The Australian sharemarket finished flat on Wednesday, as investors remained focused on the release of jobs data in the United States later this week.

In choppy trade - markets almost hit Tuesday's close at noon before sinking lower and then rising again - the ASX200 barely moved, down 2 index points (less than 0.1 per cent) to 5759.7, while the broader All Ordinaries index lost 2.5 index points to 5799.5.

Friday will see the release of non-farm payrolls data in the US, a key set of numbers ahead of the Federal Reserve's March meeting next week. Unless that's "a complete shocker, we'll see the Federal Reserve move on interest rates next week," said Citi director in equity sales Karen Jorritsma. "Other than that, it's pretty flat. There's not a whole lot going on.

"Everyone apart from materials is having a better day, but materials are a bit soft after some commodity moves overnight."

The 0.8 per cent drop in the materials sector was the biggest single drag on the index, with major miners like Rio Tinto and BHP down 0.4 and 1.1 per cent, respectively. Copper miner Oz Minerals shed 1.8 per cent, after the copper price slid 1.5 per cent overnight. Brent crude oil and steam coal fell 0.7 per cent and 1.2 per cent overnight, while iron ore bucked the trend, up slightly. 

The gold price steadied at $US1217 an ounce but gold miners still fell, with the All Ordinaries gold index losing 0.7 per cent, its fourth day in the red. Evolution Mining fell 2 per cent and Northern Star Resources lost 2.3 per cent. 

Bellamy's shares were the day's biggest loser by percentage, hitting a one-month low after sliding 3.9 per cent. It came after law firm Maurice Blackburn said it was filing a class action against it in court. Vitamins company Blackmores shed 1.1 per cent. 

Brambles, Healthscope and Isentia traded lower after moving ex-dividend, down 1.4, 3.1 and 2.4 per cent, respectively. 

Domino's shares enjoyed a slight boost, closing up 0.4 per cent after the company announced it would audit all of its 740 franchised stories by the end of June to ensure compliance with labour regulations. CSL was one of the day's outperformers among blue chips, up 0.8 per cent, followed by Cochlear, which closed up 0.7 per cent higher.  

The financials sector was well-supported, with the big four banks up between 0.7 and 0.9 per cent, with the exception of the Commonwealth Bank, which closed 0.4 per cent lower. 

Stock watch: Network Ten

Shares in Network Ten bounced slightly off an all-time low on Wednesday, closing up 3.8 per cent to 54.5¢ after hitting an all-time low of 52¢ on Tuesday. This week's sell-off appears to be linked to a large institutional investor selling out of the television station. Shares were at 92¢ before a profit warning on February 17, and have since tumbled over 40 per cent. Since last Wednesday an institutional trader with Sydney brokerage CCZ Statton equities has sold about 810,000 shares on behalf of a client, according to trading information provided by Bloomberg. This suggests an institutional shareholder has been selling out, but Ten has not yet issued any change in substantial holding notices. Analysts remain highly divided on the stock, which is mostly held by a handful of large shareholders. 

Market movers

Chinese trade

China recorded its first yuan-denominated trade deficit in three years, as imports in February surged 45 per cent from a year earlier, while exports rose only 4.2 per cent year. That left a trade deficit of 60.4 billion yuan ($US11.5 billion). Despite "skewed" numbers due to the timing of this year's week-long Lunar New Year holidays, economists said that both exports and imports still strengthened at the start of 2017. China's iron ore imports rose to 83.49 million tonnes in February, up 13 per cent from a year ago. The Aussie dollar dipped briefly on the trade figures before recovering back to just below US76¢.

Iron ore

Heavy rainfall will continue to crimp Australian iron ore exports, lending further support to prices, Macquarie predicts. After an exceptionally wet summer in WA, annualised shipments from WA's Pilbara iron ore region fell by more than 100 million tonnes in early February, the bank has calculated. The significant decline in the pace of shipments in January and February, based on weekly data from key ports, is likely to have contributed to recent strength in iron ore prices, Macquarie analyst Hayden Bairstow said. "The wet season is far from over," he said. Iron ore futures were up 0.8 per cent at 667 yuan.

Housing affordability

Housing affordability worsened in the December quarter as the average proportion of household income required to meet loan repayments rose back towards recent peaks. Rising mortgage sizes more than offset the effect of low interest rates and modestly rising wages to push the figure up 0.9 percentage points to 30.4 per cent - of a $1681 median weekly family income - the latest Adelaide Bank/REIA Housing Affordability Report says. Rental affordability also worsened, with the average proportion of income needed to meet rental payments rising to 24.4 per cent from 24.2 per cent in the September quarter.

Bubs up

Shares in baby food maker Bubs Australia spiked as much as 16.2 per cent on news its tins of infant formula will be stocked by discount wholesale retailer Costco. Bubs, which is aggressively expanding its footprint, said it has entered a supply agreement to have its infant formula milk featured in Costco's catalogue nationally and to display its products in Costco's Auburn warehouse in Sydney. Shares in the company, which listed earlier this year, ended 5.4 per cent higher at 19.5 cents.